tomfoolery
Silly, playful behavior that annoys people but is mostly harmless.
Tomfoolery means silly, foolish behavior or playful mischief. When your teacher catches you and your friends making funny faces behind her back, that's tomfoolery. When kids stuff their cheeks with grapes to look like chipmunks at the lunch table, that's tomfoolery too.
The word has a lighthearted, old-fashioned ring to it. It suggests harmless pranks and goofing around rather than serious troublemaking. If you're pelting your brother with wadded-up paper during homework time, an exasperated parent might say, “Enough of this tomfoolery!” They're annoyed, but the word itself admits there's something almost charming about your nonsense.
Tomfoolery sits somewhere between innocent fun and actual misbehavior. It's the kind of silliness that makes everyone laugh (eventually), even if it disrupts things temporarily. A class clown engaging in tomfoolery might balance a pencil on their nose or make weird sound effects, testing the teacher's patience but not actually being cruel or destructive. The word captures that universal kid experience of knowing you should settle down, but the urge to be ridiculous is just too strong.